Work machines, such as excavators, backhoes, skid steers, dozers, front-end loaders, track type machines, on-road trucks, off-road trucks, motor graders, industrial mining equipment, and the like may be used in mining, construction, agriculture, petroleum, and other such applications. During operation, a work site environment may include increased levels of background noise associated with work machine engine noise, active work tool noise and other such noise generated by equipment in and around the work site. Furthermore, ground personnel such as spotters, laborers, technicians and the like may be present around the work site. In some cases the ground personnel work in close proximity and along with the one or more work machines. As a result, clear communication between the operator of the work machine and variety of ground personnel present is important to perform different tasks or operations and ensure safety of all personnel present in and around the work site.
Background noise present around the work site can make communication difficult between ground personnel and operators of work machines. In some cases, unassisted verbal communication between individuals is not practical because work machine operators often reside within an enclosed operator compartment which somewhat isolates them from environmental noise, including verbal communication, around the work site. Furthermore, the quality of communication between work machine operators and ground personnel using an assisted communication device (e.g., hand-held radio, cellular telephone, push-to-talk cellular communication) is poor because the device simultaneously transmits the background noise along with verbal communication. Additionally, ground personnel may often need use of their hands to perform a variety of tasks around the work site which can make use of an assisted communication device difficult. As such, the desired verbal communication is often obscured or otherwise overpowered by the background noise and the recipient fails to clearly receive and understand the intended message. As a result, it may be desirable to integrate a communication system with the work machine to directionally detect and capture sound from around the work site. Moreover, the integrated system may further process the captured sound to separate desired sound (e.g., verbal communication) from undesired sound (e.g., engine noise) such that a clear line of communication is established between the work machine operator and ground personnel.
A device for reducing noise in operator compartment of construction equipment is disclosed in Chinese Patent Application Publication No. CN 204143871 U entitled, “Active noise cancelling device of engineering machinery operating room and rock drilling machine,” (the '871 publication). The noise cancelling device disclosed therein includes an acquisition device having a plurality of microphones which are configured to collect noise from outside the operator compartment. The collected noise is filtered and processed by a signal processor which outputs an inverted signal having the same frequency as the filtered collected noise. The inverted signal is amplified and output through a sound unit and used to cancel the outside noise within the operator compartment.
While arguably effective for its intended purpose, the prior art continues to need improvement in detecting, filtering and transmitting desired sound within an operator compartment.